Nic Magdalinos ran the successful practice for nine years, but died suddenly last October.
The past nine months has seen the respected architect practice continue to operate under the trusted care of three senior architects, Ian Seddon, Ezra Kelly and Chris Ainsworth.
"The three of us and our Napier team are really looking forward to being part of the DGSE group," Seddon said.
"We have worked together on many projects over the years throughout New Zealand and shared ideas and resources, so merging our practices together really is the next progression.
"We can only go from strength to strength. The entire team feels really happy with the move, and excited at what the future holds."
Designgroup PMA will continue under the ownership of DGSE with managing director Nigel Dong and fellow directors Elliott and Mike Evans. DGSE will have offices in Wellington, Palmerston North, Auckland and now Napier.